Impact of bronchoalveolar lavage lymphocytosis on the effects of anti-inflammatory therapy in idiopathic non-specific interstitial pneumonia, idiopathic pleuroparenchymal fibroelastosis, and unclassifiable idiopathic interstitial pneumonia.

BACKGROUND: Idiopathic non-specific interstitial pneumonia (iNSIP), idiopathic pleuroparenchymal fibroelastosis (iPPFE), and unclassifiable idiopathic interstitial pneumonia (IIP) are IIPs with chronic fibrotic phenotypes, and unlike idiopathic pulmonary fibrosis, they have often been treated with anti-inflammatory drugs, including corticosteroids and immunosuppressants. However, the impact of bronchoalveolar lavage (BAL) lymphocytosis on the effects of anti-inflammatory therapy has never been evaluated. This study aimed to elucidate whether BAL lymphocytosis can be used to predict the efficacy of anti-inflammatory drugs for iNSIP, iPPFE, and unclassifiable IIP. METHODS: Japanese patients diagnosed with iNSIP, iPPFE, and unclassifiable IIP by multidisciplinary discussion were identified using the nationwide registry. Eligible patients were stratified into four groups with and without BAL lymphocytosis and anti-inflammatory therapy to compare overall survival (OS) and changes in lung function. BAL lymphocytosis was defined as a lymphocyte differential count > 15%, and the cut-off was corroborated by survival classification and regression tree analysis. RESULTS: Overall, 186 patients (37 iNSIP, 16 iPPFE, and 133 unclassifiable IIP) were analyzed. Limited to patients treated with anti-inflammatory drugs (n = 123), patients with BAL lymphocytosis had a better prognosis [hazard ratio (HR), 0.26; 95% confidence interval (CI), 0.11-0.63; P = 0.003], higher slope of forced vital capacity (FVC) % predicted for 2 years, and longer OS (log-rank test, P = 0.012) than those without BAL lymphocytosis. On multivariate analysis, BAL lymphocytosis (HR 0.31; 95% CI 0.13-0.75; P = 0.009) was a prognostic factor for OS, along with age and FVC % predicted. Conversely, for patients managed without anti-inflammatory therapy (n = 63), the presence or absence of BAL lymphocytosis had no prognostic value. CONCLUSIONS: BAL lymphocytosis is associated with good outcomes in patients treated with anti-inflammatory drugs, but has no prognostic value when anti-inflammatory drugs are not used. BAL lymphocytosis may provide a predictive biomarker for identifying patients with iNSIP, iPPFE and unclassifiable IIP who are likely to benefit from anti-inflammatory drugs.

Comparison of anti-aminoacyl-tRNA synthetase antibody-related and idiopathic non-specific interstitial pneumonia.

BACKGROUND AND PURPOSE: Patients with anti-aminoacyl-tRNA synthetase (ARS) antibodies frequently experience complications of interstitial pneumonia (ARS-IP), and the computed tomography (CT) of ARS-IP frequently shows nonspecific interstitial pneumonia (NSIP) pattern. The CT pattern of ARS-IP might be different from that of idiopathic IP. However, the clinical differences in patients with ARS-IP and idiopathic IP showing the similar CT patterns have not yet been well studied. The objective of this study was to evaluate the clinical differences between patients with ARS-NSIP and idiopathic NSIP (I-NSIP). METHODS: Two groups of 34 patients each, with ARS-NSIP and I-NSIP, who visited Hiroshima University Hospital between January 2005 and December 2017, were enrolled. Clinical features and outcomes were retrospectively compared between the two groups. RESULTS: The ARS-NSIP group included more female patients and significantly younger patients than the I-NSIP group. The percentage of lymphocytes in bronchoalveolar lavage fluid (BALF) was significantly higher, and the CD4/CD8 ratio in BALF was significantly lower in the ARS-NSIP group compared with the I-NSIP group. The proportion of patients with traction bronchiectasis detected by CT was significantly higher in I-NSIP compared with ARS-NSIP. The number of patients who received corticosteroid and/or immunosuppressant therapy was significantly larger in the ARS-NSIP group than in the I-NSIP group. In addition, the patients in the I-NSIP group who underwent the immunosuppressive therapy demonstrated shorter survival than those who underwent no treatment; this tendency was not observed in the ARS-NSIP group. The 10-year survival rate of patients in the ARS-NSIP group was significantly higher than that of patients in the I-NSIP group (91.8% vs. 43.0%; log-rank, p = 0.012). The multivariate survival analysis revealed that positive anti-ARS antibody was an independent favorable prognostic factor in the patients with NSIP (OR, [95% CI]:0.12 [0.02-0.55], p = 0.013). CONCLUSIONS: Patients with ARS-NSIP had a significantly better prognosis than those with I-NSIP; this may be associated with the sensitivity to immunosuppressive therapies, and the different findings of BALF and HRCT between the two groups.

Prevalence of Myositis-Specific Antibodies in Idiopathic Interstitial Pneumonias.

Although included in the serological domain of the 'interstitial pneumonia with auto-immune features' (IPAF) research statement, the search for myositis-specific antibodies (MSA) is not incorporated in routine clinical practice. The objective of the study was to evaluate MSA prevalence in an idiopathic interstitial pneumonia (IIP) cohort (n = 68) with suggestive morphological interstitial lung disease patterns. Twelve of 68 patients (17.6%) carried MSA, whereof only two were anti-nuclear antibody-positive. Besides female gender, no demographic or pulmonary function parameter was predictive for MSA positivity. MSA were present in 32.4% of IPAF patients (n = 37), being essential for IPAF diagnosis in four of them (10.8%).

Distinct Profiles of CD163-Positive Macrophages in Idiopathic Interstitial Pneumonias.

BACKGROUND: The types of cells most significantly linked to individual subtypes of idiopathic interstitial pneumonias (IIPs) remain unclear. Few studies have examined CD163+ macrophages in IIPs. OBJECTIVE: We retrospectively aimed to immunohistochemically characterize the CD163+ macrophages in IIPs. METHODS: Paraffin-embedded lung tissue samples were obtained from 47 patients with IIPs, including idiopathic pulmonary fibrosis (IPF), idiopathic nonspecific interstitial pneumonia (NSIP), and cryptogenic organizing pneumonia (COP), and 12 normal controls were immunohistochemically analyzed, using primary antibodies against CD68 and CD163 as indicators of pan and M2 macrophages, respectively. RESULTS: CD68+ macrophage density was significantly increased in the 3 subtypes of IIPs relative to that in the control group, although no difference was detected within the different IIPs. CD163+ macrophage density was significantly increased in NSIP and COP samples relative to that in IPF samples. The density ratio of CD163+ macrophages to CD68+ macrophages was significantly decreased in IPF/UIP samples relative to that in the others, while the densities in NSIP and COP were significantly higher than those in control cases. CONCLUSION: CD163+ macrophages show distinct profiles among IIPs, and the standardized numerical density is decreased in IPF cases that have poor prognoses.

Histological variability and consequences in chronic bird-related hypersensitivity pneumonitis.

BACKGROUND AND OBJECTIVE: Lobar and temporal histological variability in chronic bird-related hypersensitivity pneumonitis (BRHP) has not been clearly elucidated. This study was designed to evaluate the spatio-temporal histopathological variability in chronic BRHP. METHODS: Fifty-two patients with chronic BRHP who underwent a surgical lung biopsy (SLB) between 1992 and 2008 were evaluated. The histopathological characteristics of the lung biopsy specimens were classified by the 2002 American Thoracic Society/European Respiratory Society (ATS/ERS) consensus classification of idiopathic interstitial pneumonias (IIPs). Autopsy specimens from seven patients were also evaluated to examine the serial changes from SLB to autopsy. RESULTS: In a study of lobar histological variability based on the findings of SLB, 7 patients were diagnosed with cellular nonspecific interstitial pneumonia (NSIP) pattern, 16 with fibrotic NSIP pattern, 20 with fibrotic NSIP pattern and usual interstitial pneumonia (UIP) (discordant UIP) pattern and 9 with UIP (concordant UIP) pattern. In a study of sequential changes, specimens of SLBs with fibrotic NSIP pattern changed to a bronchiolocentric interstitial pneumonia (BIP) pattern or UIP pattern. CONCLUSION: Interlobar and intralobar histological variability is present in chronic BRHP. In several patients with chronic BRHP, a fibrotic NSIP pattern may be an early lesion that progresses to a UIP pattern.

Idiopathic Interstitial Pneumonia Associated With Autoantibodies: A Large Case Series Followed Over 1 Year.

BACKGROUND: Some patients with autoimmune characteristics and idiopathic interstitial pneumonia, particularly usual interstitial pneumonia (UIP), do not fit neatly into the category of connective tissue disease-associated interstitial lung disease (CTD-ILD), idiopathic pulmonary fibrosis (IPF), or recently proposed yet to be validated criteria for interstitial pneumonia with autoimmune features (IPAF). Outcomes of these patients are unknown. METHODS: This was a retrospective single-center study. Analyses of variance compared differences in mean change in FVC and diffusion capacity (Dlco) over 1 year among 124 well-defined patients (20 patients with positive autoantibodies with or without symptoms of connective tissue disease [AI-ILD], 15 patients with IPAF, 36 patients with CTD-ILD, and 53 patients with IPF with negative CTD serologies [Lone-IPF]). RESULTS: Of the patients, 75% with AI-ILD, 33% with IPAF, and 33% with CTD-ILD had UIP. Initial FVC and Dlco were similarly moderately reduced across groups. Mean change in FVC over 12 months was as follows: -60 mL (IPAF), -110 mL (AI-ILD), -10 mL (CTD-ILD), and -90 mL (Lone-IPF) (P = .52). Mean change in Dlco was as follows: 2.39 mL/mm Hg/min (IPAF), -1.15 mL/mm Hg/min (AI-ILD), -0.27 mL/mm Hg/min (CTD-ILD), and -1.05 mL/mm Hg/min (Lone-IPF) (P < .001). By pattern of disease, the mean change in FVC was as follows: -140 mL (UIP), 10 mL (nonspecific interstitial pneumonia), and 12 mL (unclassifiable/other) (P = .001). CONCLUSIONS: No clinically significant differences in pulmonary function to distinguish between patients with AI-ILD, IPAF, CTD-ILD, and Lone-IPF were observed after 1 year. Longer periods of follow-up are needed to understand the outcomes of these patients. It is not yet clear whether AI-ILD is a distinct phenotype or a variant of the newly proposed entity IPAF.

Clinical Features of Idiopathic Interstitial Pneumonia with Systemic Sclerosis-Related Autoantibody in Comparison with Interstitial Pneumonia with Systemic Sclerosis.

BACKGROUND: Patients with idiopathic interstitial pneumonias sometimes have a few features of connective tissue disease (CTD) and yet do not fulfil the diagnostic criteria for any specific CTD. OBJECTIVE: This study was conducted to elucidate the characteristics, prognosis, and disease behavior in patients with interstitial lung disease (ILD) associated with systemic sclerosis (SSc)-related autoantibodies. METHODS: We retrospectively analyzed medical records of 72 ILD patients: 40 patients with SSc (SSc-ILD) and 32 patients with SSc-related autoantibody-positive ILD but not with CTD (ScAb-ILD), indicating lung-dominant CTD with SSc-related autoantibody. RESULTS: Patients with SSc-ILD were predominantly females and non-smokers, and most had nonspecific interstitial pneumonia confirmed by high-resolution computed tomography (HRCT) and pathological analysis. However, about half of the patients with ScAb-ILD were male and current or ex-smokers. On HRCT analysis, honeycombing was more predominant in patients with ScAb-ILD than with SSc-ILD. Pathological analysis showed the severity of vascular intimal or medial thickening in the SSc-ILD patients to be significantly higher than that in the ScAb-ILD patients. Survival curves showed that the patients with ScAb-ILD had a significantly poorer outcome than those with SSc-ILD. CONCLUSION: Data from this study suggest that lung-dominant CTD with SSc-related autoantibody is a different disease entity from SSc-ILD.

Characterisation of patients with interstitial pneumonia with autoimmune features.

Patients with interstitial lung disease (ILD) may have features of connective tissue disease (CTD), but lack findings diagnostic of a specific CTD. A recent European Respiratory Society/American Thoracic Society research statement proposed criteria for patients with interstitial pneumonia with autoimmune features (IPAF).We applied IPAF criteria to patients with idiopathic interstitial pneumonia and undifferentiated CTD-ILD (UCTD). We then characterised the clinical, serological and morphological features of the IPAF cohort, compared outcomes to other ILD cohorts and validated individual IPAF domains using survival as an endpoint.Of 422 patients, 144 met IPAF criteria. Mean age was 63.2 years with a slight female predominance. IPAF cohort survival was marginally better than patients with idiopathic pulmonary fibrosis, but worse than CTD-ILD. A non-usual interstitial pneumonia pattern was associated with improved survival, as was presence of the clinical domain. A modified IPAF cohort of those meeting the clinical domain and a radiographic or histological feature within the morphological domain displayed survival similar to those with CTD-ILD.IPAF is common among patients with idiopathic interstitial pneumonia and UCTD. Specific IPAF features can identify subgroups with differential survival. Further research is needed to replicate these findings and determine whether patients meeting IPAF criteria benefit from immunosuppressive therapy.

Clinical Utility of an Enzyme-Linked Immunosorbent Assay for Detecting Anti-Melanoma Differentiation-Associated Gene 5 Autoantibodies.

OBJECTIVE: Autoantibodies to melanoma differentiation-associated gene 5 (MDA5) are specifically expressed in patients with dermatomyositis (DM) and are associated with a subset of DM patients with rapidly progressive interstitial lung disease (RP-ILD). Here, we examined the clinical utility of a newly developed enzyme-linked immunosorbent assay (ELISA) system for detecting these antibodies. METHODS: Here we developed an improved ELISA for detecting anti-MDA5 antibodies. We then performed a multicenter clinical study involving 8 medical centers and enrolled 242 adult patients with polymyositis (PM)/DM, 190 with non-PM/DM connective tissue disease (CTD), 154 with idiopathic interstitial pneumonia (IIP), and 123 healthy controls. Anti-MDA5 antibodies in the patients' serum samples were quantified using our newly developed ELISA, and the results were compared to those obtained using the gold-standard immunoprecipitation (IP) assay. In addition, correlations between the ELISA-quantified anti-MDA5 antibodies and clinical characteristics were evaluated. RESULTS: In patients with PM/DM, the anti-MDA5 antibody measurements obtained from the ELISA and IP assay were highly concordant; the ELISA exhibited an analytical sensitivity of 98.2%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 99.5% (compared to the IP assay). Anti-MDA5 antibodies were detected in 22.7% of the DM patients, but not in any of the patients with PM, non-PM/DM CTD, or IIP. Clinically amyopathic DM, RP-ILD, arthritis, and fever were more prevalent in DM patients who were anti-MDA5 antibody-positive than in those who were antibody-negative (P ≤ 0.0002 for all comparisons). In addition, anti-MDA5 antibody-positive patients with RP-ILD exhibited higher antibody levels than those without RP-ILD (P = 0.006). CONCLUSION: Our newly developed ELISA can detect anti-MDA5 antibodies as efficiently as the gold standard IP assay and has the potential to facilitate the routine clinical measurement of anti-MDA5 antibodies in patients who suspected to have DM.

Coexistence of Autoantibodies against the Golgi Complex and Ro52 Antigen in a Patient with Nonspecific Interstitial Pneumonia.

Nonspecific interstitial pneumonia (NSIP) is often associated with connective tissue diseases (CTD). The diagnosis of NSIP was confirmed in a 63-year-old man by high-resolution computed tomography and an open lung biopsy. Anti-Golgi complex autoantibodies (AGA) and anti-Ro52 antibodies were simultaneously detected at high concentrations. Autoantibodies to aminoacyl-tRNA synthetases (ARS) were negative. The patient was treated with corticosteroids for six months. During the seven-year follow-up, NSIP had a slow progression and patient had not developed the clinical features of CTD. The present study potentially demonstrates that the autoimmune process elicited by AGA and/or Ro/SSA may play a role in promoting idiopathic NSIP independently of the typical ARS routes, which has not been reported thus far.

Clinical Implication of Proteinase-3-antineutrophil Cytoplasmic Antibody in Patients with Idiopathic Interstitial Pneumonias.

PURPOSE: The clinical significance of proteinase-3-antineutrophil cytoplasmic antibody (PR3-ANCA) positivity is not well established in idiopathic interstitial pneumonia (IIP) patients. We aimed to determine the clinical features of PR3-ANCA-positive IIP patients. METHODS: We retrospectively reviewed 377 consecutive IIP patients; of these, 360 patients had PR3-ANCA and myeloperoxidase-antineutrophil cytoplasmic antibody test results available. The clinical features of PR3-ANCA-positive IIP patients and control ANCA-negative idiopathic pulmonary fibrosis patients (ANCA-negative IPF) were compared. RESULTS: Sixteen patients (4.4 %) were PR3-ANCA-positive IIP and 94 (26 %) were ANCA-negative IPF. The median age at diagnosis (72 vs. 70 years, P = 0.17) and proportion of males (75 vs. 89 %, P = 0.12) in PR3-ANCA-positive IIP and ANCA-negative IPF patients, respectively, were not significantly different. Radiologically, the HRCT patterns of PR3-ANCA-positive IIP patients varied (UIP, n = 3, 18.8 %; possible UIP, n = 3, 18.8 %; NSIP, n = 5, 31.3 %; unclassifiable CT pattern, n = 5, 31.3 %) more than those of ANCA-negative IPF patients (UIP, n = 69, 73.4 %; possible UIP, n = 25, 26.6 %; P < 0.001). No PR3-ANCA-positive IIP patients developed ANCA-associated vasculitis. The 5-year survival rate was 50 % in PR3-ANCA-positive IIP patients and 52 % in ANCA-negative IPF patients with no significant difference (P = 0.96 by log-rank test). CONCLUSIONS: The HRCT patterns of PR3-ANCA-positive IIP patients varied more than those of the IPF patients, but the clinical features of high IIP-onset age and male predominance were similar between the groups. Furthermore, PR3-ANCA-positive IIP patients had a poor prognosis similar to that of IPF patients.

Nonspecific interstitial pneumonia: survival is influenced by the underlying cause.

Idiopathic, nonspecific interstitial pneumonia (NSIP) is most often associated with various clinical disorders, including connective tissue diseases (CTDs) and chronic hypersensitivity pneumonitis (cHP). Emerging evidence also suggests that "idiopathic" NSIP may be the lung manifestation of undifferentiated CTD (UCTD). However, whether or not NSIP outcome is influenced by the underlying cause remains uncertain. This retrospective study included 127 biopsy-proven NSIP patients (65 women, mean ± sd age 55 ± 12 years). Survivals were estimated using a Kaplan-Meier curve and compared using the log-rank test. Multivariate analyses were based on a Cox model. 15 (11.8%) patients had cHP, 29 (22.8%) had CTD, 32 (25.2%) satisfied the Kinder criteria for UCTD and 51 (40.1%) had idiopathic NSIP. At the end of follow-up (mean ± sd 64 ± 54 months), a difference in survival was observed between aetiological groups (p=0.002). Survival was better for UCTD than for idiopathic NSIP (p=0.020) and similar to that observed for CTD. cHP survival tended to be poorer than that of idiopathic NSIP (p=0.087) and was an independent predictor of mortality (hazard ratio 2.17, 95% CI 1.05-4.47; p=0.035). NSIP outcome is influenced by its cause. cHP exhibits the highest mortality. UCTD does not differ from CTD supporting the concept of autoimmune NSIP, with a prognosis that is better than that of idiopathic NSIP.

Innate immunity alterations in idiopathic interstitial pneumonias and rheumatoid arthritis-associated interstitial lung diseases.

BACKGROUND: This is a prospective cohort study elucidating innate immunity in idiopathic pulmonary fibrosis (IPF), cryptogenic organizing pneumonia (COP), rheumatoid arthritis-associated usual interstitial pneumonia (RA-UIP) and RA-associated non specific interstitial pneumonia (RA-NSIP). METHODS: 23 IPF subjects, 9 COP subjects, 5 RA-UIP subjects, 8 RA-NSIP subjects were enrolled. 10 subjects were excluded. 19 healthy subjects served as controls. Blood and bronchoalveolar lavage (BAL) were obtained. Natural killer (NK) and NKT cells, NK cells apoptosis and the expression of triggering receptor expressed on myeloid cells type 1 (TREM-1) were assessed. Tumor necrosis factor-α (TNF-α) production was measured in cell cultures after stimulation with lipopolysaccharide endotoxin (LPS) and Pam3CysSK3, and in BAL. Surface expression of Toll-like receptors (TLR) 2 and 4 on peripheral blood monocytes (PBMC's) and circulating NK cells was also assessed. RESULTS: RA-NSIP had low blood NKs, marginally insignificant (p=0.07). These NKs poorly produced TNF-α after LPS stimulation. TLR's expression on NK cells was similar throughout disease groups and controls. PBMC's mainly from IPF patients exhibited low TNF-α production after LPS stimulation but not after Pam3CysSK3 stimulation, while TLR4 expression on PBMC's was found normal in all study groups. TLR2 expression on PBMC's was increased in IPF, but mainly in COP, RA-UIP and RA-NSIP (p=0.015). TREM-1 expression was significant on COP monocytes and on COP neutrophils versus controls. RA-NSIP monocytes also exhibited TREM-1 expression (p=0.07). Decreased TNF-α concentration in BAL was finally observed in IPF and RA-UIP. CONCLUSIONS: Innate immunity in the lungs and the peripheral circulation in IPF and RA-UIP are similar and more fibrotic than in RA-NSIP which is characterized by NK cell depletion and dysfunction. TREM-1 and TLR's likely affect patterns of inflammation in various interstitial lung diseases.

CD4+ and CD8+ T lymphocytes in lung tissue of NSIP: correlation with T lymphocytes in BALF.

BACKGROUND: Nonspecific interstitial pneumonia (NSIP) is characterized by the interstitial infiltration T lymphocytes (TLs). Bronchoalveolar lavage fluid (BALF) has been used to analyze the inflammatory cells infiltrating in lung. The controversy about whether the BALF cellular profile reflects T lymphocytes in lung tissue still persists. Some studies found a positive correlation of cell composition between BALF and lung tissue, but others gave opposite conclusion. OBJECTIVE: To investigate CD4+ and CD8+ T lymphocytes distribution in lung tissue of NSIP and the relationship with T lymphocytes in bronchoalveolar lavage. METHODS: Thirty-seven patients diagnosed as NSIP were included. The pathological and BALF date were reviewed. The characteristics of TLs infiltration in different lung regions were investigated. RESULTS: The study included 28 women. The median age was 48 years. In lung tissue, CD4+ and CD8+ lymphocytes (counts/0.1mm2) were separately accounted in lymphoid follicle region (156.51 ± 90.70 vs 85.30 ± 43.75), small blood vessel region (66.58 ± 31.99 vs 58.43 ± 30.24), interstitial region (37.60 ± 19.40 vs 47.12 ± 33.42) and small airway region (26.59 ± 17.04 vs 40.18 ± 34.02). CD4+/CD8+ ratios in lymphoid follicle and small vessel > 1, in interstitium and small airway <1. The number of CD8+ lymphocytes in BALF was correlated with CD8+ lymphocytes around small airway (r = 0.360, p = 0.029) and in interstitial region (r = 0.451, p = 0.005). CD4+/CD8+ ratio in BALF was correlated with that in small airway region (r = 0.437, p = 0.007) and interstitial region (r = 0.468, p = 0.003). CONCLUSIONS: In NSIP, T lymphocytes were distributed in different regions of lung tissue. The CD8+ T lymphocytes and CD4+/CD8+ ratio in BALF reflect those in interstitium regions and around small airway of the lung.

Idiopathic pneumonia syndrome in mice after allogeneic bone marrow transplantation: association between idiopathic pneumonia syndrome and acute graft-versus-host disease.

OBJECTIVE: To explore the association between idiopathic pneumonia syndrome (IPS) and acute graft-versus-host disease (aGVHD) in allogeneic hematopoietic stem cell transplantation. METHODS: Established acute GVHD model of C57BL/6-->BALB/c mice. Chest computed tomography (CT) scans were dynamically performed in recipient mice after transplant. Lung histopathology and cytokine levels (including TNF-alpha and IFN-gamma) were examined in three experimental groups: mice receiving simple irradiation, syngeneic transplants, and allogeneic transplants. RESULTS: All allogeneic transplant mice developed aGVHD. On CT, most aGVHD mice had bilateral diffuse lung infiltrates, while syngeneic transplant mice had normal lungs. On histopathology, aGVHD mice had acute pneumonitis. On immunohistochemistry, the infiltrates were mainly CD4+ T cells during aGVHD onset, but CD8+ T cells predominated during aGVHD progression. Lung TNF-alpha and IFN-gamma levels were higher in the three experimental groups than in normal controls on days +3 and +7 post-transplant. On day +7, TNF-alpha levels were higher in allogeneic than in syngeneic transplant mice; IFN-gamma levels were not different. On days +12 and +16, TNF-alpha levels were higher but IFN-gamma levels were lower in allogeneic mice than in syngeneic transplant mice. CONCLUSIONS: The underlying cause of IPS is aGVHD. T cells and TNF-alpha may play a role in the pathogenesis of aGVHD-induced IPS. IPS progression may be associated with decreasing lung IFN-gamma levels.

Nonspecific interstitial pneumonia (NSIP) associated with anti-KS antibody: differentiation from idiopathic NSIP.

We report two cases of biopsy-proven nonspecific interstitial pneumonia (NSIP) with anti-KS (asparaginyl-tRNA) antibody. Anti-KS antibody is the sixth anti-aminoacyl-tRNA synthetase (ARS) antibody. They showed interstitial pneumonia without clinical symptoms, and high resolution computed tomography (HRCT) of the chest demonstrated consolidation along bronchovascular bundles and volume loss in the bilateral lower lobes, which were suggestive of connective tissue diseases (CTD). One case of cellular NSIP responded to corticosteroid, but the other case of fibrotic NSIP required corticosteroid and cyclosporin. In patients with these HRCT findings, the measurement of anti-ARS antibodies could be helpful even in the absence of clinical symptoms suggestive of CTD.

TLR9 is expressed in idiopathic interstitial pneumonia and its activation promotes in vitro myofibroblast differentiation.

Infectious diseases can be cofactors in idiopathic interstitial pneumonias (IIP) pathogenesis; recent data suggests that toll-like receptors 9 (TLR9) ligands contribute to experimental chronic tissue remodeling. Real-time TAQMAN and immunohistochemical analysis of IIP normal surgical lung biopsies (SLBs), primary fibroblast lines grown from both IIP and normal SLBs indicate that TLR9 is prominently and differentially expressed in a disease-specific manner. TLR9 expression was increased in biopsies from patients with IIP compared with normal lung biopsies and its expression is localized to areas of marked interstitial fibrosis. TLR9 in fibroblasts appeared to be increased by profibrotic Th2 cytokines (IL-4 and IL-13) and this was true in fibroblasts cultured from the most severe form of IIP, idiopathic pulmonary fibrosis (IPF) SLBs, in non-specific interstitial pneumonia fibroblast lines, and in normal fibroblasts. Finally, confocal microscopy studies have shown that TLR9 activation by its synthetic agonist CpG-ODN significantly increased the expression of alpha smooth muscle actin, the main marker of myofibroblast differentiation. These data indicate that TLR9 expression may drive the abnormal tissue healing response in severe forms of IIP and its activation can have a key role in myofibroblast differentiation promoting the progression of disease during the terminal phase of IPF.

Immunophenotyping and remodeling process in small airways of idiopathic interstitial pneumonias: functional and prognostic significance.

BACKGROUND AND AIMS: To test whether different degrees of immunologic and fibrotic airway remodeling processes occur in idiopathic interstitial pneumonias (IIPs), with impact on functional tests and survival, we studied the collagen/elastic system and immune cell density in the bronchiolar interstitium of lungs with the major types of IIPs. MATERIALS AND METHODS: Histochemistry, immunohistochemistry and morphometric analysis were used to evaluate collagen/elastic fibers and immune cells in the bronchiolar interstitium of open lung biopsies of patients with cryptogenic organizing pneumonia [COP/organizing pneumonia (OP) = 10], acute interstitial pneumonia [AIP/diffuse alveolar damage (DAD) = 20], nonspecific interstitial pneumonia (NSIP/NSIP = 20) and idiopathic pulmonary fibrosis/usual interstitial pneumonia (UIP) = 20. RESULTS: OP lungs presented a significant increase in collagenous/elastic fibers and in the total density of immune cells in the bronchiolar interstitium compared to controls, DAD, NSIP and UIP. We observed a significant increase in CD4, CD8 and CD20 lymphocytes, as well as in neutrophils, macrophages and plasma cells in OP. The increased amount of elastic fibers in the bronchiolar interstitium from OP lungs has a direct association with forced vital capacity (FVC) (r(s) = 0.99, P = 0.03). The most important survival predictor was CD20+ lymphocytes in the bronchiolar interstitium. In decreasing order, patients with UIP [Odds Ratio (OR) = 35.01], high forced expiratory volume in 1 s (FEV(1))/FVC FVC (OR = 7.01), increased CD20+ lymphocytes (OR = 4.44) and collagenous/elastic fiber densities (OR = 2.03 and OR = 1.49, respectively) in the bronchiolar interstitium were those who had the greatest risk of death, followed by those with AIP, NSIP and COP. CONCLUSION: Different degrees of immunologic and fibroelastotic airway remodeling processes occur in the major types of IIPs with impact on physiological tests and survival.